<template>
	<view class="u-row" ref="u-row" :style="[rowStyle]" @tap="clickHandler">
		<slot />
	</view>
</template>

<script>
// #ifdef APP-NVUE
const dom = uni.requireNativePlugin('dom')
// #endif
import props from './props.js'
import mpMixin from '../../libs/mixin/mpMixin.js'
import mixin from '../../libs/mixin/mixin.js'
/**
 * Row 栅格系统中的行
 * @description 通过基础的 12 分栏，迅速简便地创建布局
 * @tutorial https://www.uviewui.com/components/layout.html
 * @property {String | Number}	gutter		栅格间隔，左右各为此值的一半，单位px  (默认 0 )
 * @property {String}			justify		水平排列方式(微信小程序暂不支持) 可选值为`start`(或`flex-start`)、`end`(或`flex-end`)、`center`、`around`(或`space-around`)、`between`(或`space-between`)  (默认 'start' )
 * @property {String}			align		垂直排列方式 (默认 'center' )
 * @property {Object}			customStyle	定义需要用到的外部样式
 *
 * @event {Function} click row被点击
 * @example <u-row justify="space-between" customStyle="margin-bottom: 10px"></u-row>
 */
export default {
	name: 'u-row',
	// #ifndef MP
	emits: ['click'],
	// #endif
	mixins: [mpMixin, mixin, props],
	data() {
		return {}
	},
	computed: {
		uJustify() {
			if (this.justify == 'end' || this.justify == 'start') return 'flex-' + this.justify
			else if (this.justify == 'around' || this.justify == 'between') return 'space-' + this.justify
			return this.justify
		},
		uAlignItem() {
			if (this.align == 'top') return 'flex-start'
			if (this.align == 'bottom') return 'flex-end'
			return this.align
		},
		rowStyle() {
			const style = {
				alignItems: this.uAlignItem,
				justifyContent: this.uJustify
			}
			// 通过给u-row左右两边的负外边距，消除u-col在有gutter时，第一个和最后一个元素的左内边距和右内边距造成的影响
			if (this.gutter) {
				style.marginLeft = uni.$u.addUnit(-Number(this.gutter) / 2)
				style.marginRight = uni.$u.addUnit(-Number(this.gutter) / 2)
			}
			return uni.$u.deepMerge(style, uni.$u.addStyle(this.customStyle))
		}
	},
	methods: {
		clickHandler() {
			this.$emit('click')
		},
		async getComponentWidth() {
			// 延时一定时间，以确保节点渲染完成
			await uni.$u.sleep()
			return new Promise(resolve => {
				// uView封装的获取节点的方法，详见文档
				// #ifndef APP-NVUE
				this.$uGetRect('.u-row').then(res => {
					resolve(res.width)
				})
				// #endif
				// #ifdef APP-NVUE
				// nvue的dom模块用于获取节点
				dom.getComponentRect(this.$refs['u-row'], res => {
					resolve(res.size.width)
				})
				// #endif
			})
		}
	}
}
</script>

<style lang="scss" scoped>
@import '../../libs/css/components.scss';

.u-row {
	@include flex;
}
</style>
